Starting and speed-regulating rheostat.



PATENTED SEPT. 1, 1908.

I P.-J. SEABOLT. STARTING AND SPEED REGULATING RHEQSTAT.

APPLICATION FILED JAN. 25, 190B.

hwendof. Frank J. Seabolfif.

UNITED sTATEs PATENT OFFICE.

FRANK J. sic/incur, or srii-icNnc'ranv, NEW Your, AssIcNoR'ro GENERALELECTRIC coMrANY, .A GORPORATION or NEW YORK.

STARTING AND SPEED-REGULATING REEOSTAT.

To all whom it may concern:

Be it known that I, FRANK J. SEABOL'I, a citizen of the United. States,residing at Schenectady, county of Schenectady, State of New York,haveinventcd certain new and useful Improvements in Starting and Speed-Regulating Rheostats, o'l' which the following is a specification.

This invention relates to devices for controlling electric motorcircuits and has for its object the provision of a device oi thischaracter in which the starting and speed regulation of the motor may beaccomplished in a reliable, simple and'eifieient manner.

My invention relates more specifically to devices for starting a motorand thereafter varying the 'speed.

In carrying out my invention I provide in connection with starting and seed regulat,

ingresistances, a single centre ling arm arranged to control both ofsaid resistances and thereby accomplish both the starting and s eedregulation. In in revious patent 0. 852,851, I have descri ed a deviceof this character in which the controlling arm is biased to the offposition so that upon failure of'voltage it will always return to aprotective position. In this rheostat the arrange ment is such that whenthe controlling arm moves to vary the starting resistance the fieldresistance is short-circuited and while the field resistance is beingvaried the armature resistance is short-clrcuited. For certain purposesI have found that a rheostat of Patented Sept. 1, 1908.

Serial No. 412,639.

and 12 forming the terminals of the field and armature resistances 13and 14 respectively. A controlling member 15 is pivoted concentricallywith said studs so that the contacts 16 and 17 at its free end move overthe re spective studs to vary the resistance in a wellknown manner. Thehandle of the controlling member is provided with a switch comprising aplunger 18 adapted to be moved longitudinally of the handle against theten- 6:,

sion of the spring 19. This plun er. is provided at 1ts ower end with abri gin con ,tact 20 arranged to bridge contacts 21 or the Adjacent tocoils control the bridgiin contact 25 to close the armature circuit. hecoil 22 is of sufficient strength to actuate the contact 25 while thewlnding 23 is only sufiicient to hold the contactor in a raisedposition. A switch arm 26 is pivoted at 27 to the magnet frame so as tobe held aainst the tension of the sIpring 28 when t e magnet isenergized.

his arm is rovided with contact strips 29' and 30 insu ated from thearnn The strip- 29 is arranged to bridge the contact studs 31 and 32when the arm is moved into contact with the magnet while the strip 30engages the contact segment 33 at all times. When in the position shownin the drawing,:the

position of the controlling arm 70 35 this type, in which thecontrolling arm is not .biased to the off position, is desirable. I

have also found in some cases that it is objectionable to open thecircuit uponthe contact studs. I therefore provide an electromagneticswitch which always opens the circuit in addition to a controlling armwhich may be left in any osition.

Other features 0 novelty will appear in the course of thefollowing-specification in which I have shown my invention embodied inconcrete mechanism for purposes of illustration.

strip 30 engages contact stud 34 while when it is moved up against themagnet it enga es stud 35. The winding 22 is energized iy means of astud 36'arranged to be engaged by the cont-act 17 when the arm is in itsmitial position but it will be denergized after the initial movement.

The arrangement of circuits and mode of operation are as follows: when1t is desired-to start the motor the ,arm 15 is moved to the night so asto engage the studs 11,12 and 36. The winding 22 is thereupon energizedto In the accompanying drawing disclosing my invention, F1 re 1 1s aplan view of the device'showing t e circuit connections and Fig. 2 is adetail view of the controlling member partly in section.

Referring to the drawing, 10 is an insulating base ofslate or sea stoneprovided with close the switch 25 as follows: from the positive main tothe stud 36 thence through winding 22 and back to the negative mam.

The switch 25 being closed, the armature cir- 55 two sets of concentricy-arranged studs 11 At the same time the field resistance 13 is noshort-circuitd as follows: from the positive main through conductor 39,contact strip 30, conductor'40, field F and back to line. armatureresistance may now be cut out by movin'g'the arm to the right in theusual way.

When the contact 's broken at stud 36, wind ing 22 will be deenergizedbut in the mean time the plunger switch 18 in the handle has beenpressed down so as to brid e the contacts 21 thereby energizing the hoding winding 23 as follows: from the positive main to conductor 41,contact 20, conductor 42, winding 23 conductor 43 and back to thenegative main. This will hold the switch 25 closed, but if the operatorshould release the switch in the handle, thc armature circuit will beimmediately opened and it will be necessary to return the arm tostarting position in contact with the stud 36 in order to again closeit. When the arm.15 reaches running position, the switch arm 26 isforced over by the In 44 into engagement with the magnet 24. 'Ihiscauses the armature resistance to be short-circuited across from con.ductor 39 to conductor 38 by the conducting moving the arm ack andforth over the studs 11. Upon failure of voltage the armature circuitwill be opened. at switch 25 and the arm 26 will return in response tothe tension of its spring so as to open the shortcircuit of the armatureresistance and again close the short-circuit of the. field resistance.The switch 25. being opened in order to again close it, the arm must bebrought back to the startin position.

It w' 1 thus be seen that I have provided a simple and efficient arranement for both startin and regulating the speed of the motor by means ofa single controlling mem ber in addition to means for protecting therheostat from abnormal circuit conditions. 'While I have described ,minvention in connection with specific mec ianism and arrangement ofcircuits, it should be understood that I do not limit my inventionthereto sin ce various modifications will suggest themselves to thoseskilled in the art without departing from the spirit of my invention,the scope of which is set forth in the annexed claims.

\Vhat I claim as new and. desire to secure by Letters Patent ol' theUnited States, is,---

l. A controlling device for elmt-tiic motors comprising pair ofresistances each provided with contacts. a controlling member The themotor circuit through the armature resistance, and means controlledthereby for rendering said member ineffective to control one of saidresistances when moved in one direction and the other of saidresistances when. moved in the opposite direction.

3. A motor-starting and speed-regulating rheostat comprising an armatureresistance and a field resistance each provided with con tact-s, acontrolling member simultaneously engaging said contacts, anelectromagnetic device arranged to be energized upon the initialmovement of said arm for closing the motor circuit through the armatureresistance, means for shru't-cirrmitiug the field resistance, and meanscrmtrolled. by said electromag netic device for opening saidshort-circuit and simultaneously short-circuiting the armatureresistance when the controlling arm reaches running position.

4. A controlling device for electric motors comprising a pair ofresistances each provided with contacts, a controlling membersimultaneously engaging said contacts, an electromagnetic device forclosing the motor circuit through one of said resistances, a switch inconnection with said member for controlling said electroma :ncticdevice, and means controlled by said e ectromagnetio device forrendering said member ineffective to control one of said resistanceswhen moved in one direction and the other of said resistances when movedin the other direction and simultaneously short-circuiting said switch.

5. A controlling device for electric motors comprising a pair ofresistances each providcd with contacts, a controlling membersimultancou sly engaging said contacts, an electromagnetic device forclosing the motor circuit through one of said resistances upon theinitial. movement-of said member, means for rcduoing the energy of saiddevice from an ac tu ating to a holding current, andmeans controlled bysaid device for rendering said member ineffective to control one of saidresista field resistance each provided with contacts, a controllingmember simultaneously engaging said contacts, an electromagnetic devicefor closing the motor circuit through the armature resistance upon theinitial movement of said member, a switch in connection with said memberfor controllin said electromagnetic device, means controfied by saiddevice for rendering said member ineffective to control one of saidresistances-when moved in one direction and the other of saidresistances when moved in the opposite direction, and means forshort-circuiting said switch when the controlling member reaches runningposition.

I 7. A motor starting and speed regulating rheostat comprising astarting resistance and a fieldresistance each provided with contacts, acontrolling member simultaneously engaging said contacts, anelectromagnetic device for closing the motor circuit through thearmature resistance upon the initial movement of said member, means forreducing the-energy of said device from an actuating to a holdingcurrent after said initial movement, a swltch in connection with saidmember for controlli said electromagnetic device, means control ed bysaid device for rendering said member-ineffective to control one of saidresistances when moved in one direction and the other of saidresistances when moved in the opposite direction, and means forshort-circuitmg said switch when the controlling member reaches runningposition.

8. A controlling device for electric motors comprisin a pair ofresistances each provided with contacts, a controlling membersimultaneously engaging said contacts, an electromagnetic device forclosing the motor circuit through one of said resistances upon theinitial movement of said member, a switch in connection with said memberfor controlling said electromagnetic device, means for reducing theenergy of said device from an actuating to a holding current after theinitial movement of said member, and means controlled. by said devicefor rendering said member inefiective to control one of said resistanceswhen moved. in one direction. and the other of said resistances whenmoved in the opposite direction and simultaneously short-circuiting saidswitch.

9. A starting device for electric motors comprising a resistance, acontrolling member therefor, an electromagnetic device for closing themotor circuit through sa1dres1stance upon the init al movement of saidmember, a switch in connection with said member.

for controlling the circuit of said electromagnetic device, and meanscontrolled by said device for short-circuiting said switch.

10. A starting device for. electric motors comprising a resistance, acontrolling member therefor, an electromagnetic device for closingthemotor circuit through said resistance upon the initial mov ent ofsaid member, means for reducing the energy, of said device from anactuating to a holdim current after said initial movement, aswitc inconnection with said member for controlling the circuit of said device,and means controlled by said device ,for short circuiting said switch. IIn witness whereof, I have hereunto set my hand this 23rd day of J anua1908.

FRANK J. S ABOLT. Witnesses:

BENJAMIN B. HULL, HELEN Onronn.

